Study on the Effect of Dynamic Eccentricity on Acoustic Noise of an Interior Permanent Magnet Traction Motor

The modeling of acoustic noise is an important step in the design of traction motors for noise-sensitive applications. Eccentricity, which is a common type of manufacturing imperfection, can be a source of acoustic noise in traction motors. This paper presents a comprehensive analysis of the effect of dynamic eccentricity on the acoustic noise in a 48/8 interior permanent magnet traction motor. After considering the dynamic eccentricity, the extra dominant radial force harmonics are identified. The acoustic noise simulation is conducted based on a fast-numerical method, which can significantly reduce the computation cost without sacrificing the accuracy. The effect of dynamic eccentricity on the acoustic noise performance of the motor is discussed. Results show that a higher Sound Pressure Level (SPL) appears in a wider speed range when dynamic eccentricity is considered.